Genetics Quiz: DNA Structure, Genes, and Inheritance

Genetics

DNA Structure

• Double helix model: two complementary strands of nucleotides twisted together
• Nucleotides composed of:
  • Sugar molecule (deoxyribose)
  • Phosphate group
  • Nitrogenous base (A, C, G, or T)

Genes and Genomes

• Gene: a segment of DNA that codes for a protein or functional RNA
• Genome: the complete set of genes in an organism
• Humans have approximately 20,000-25,000 protein-coding genes

Mendelian Genetics

• Laws of Inheritance:
  • Law of Segregation: each pair of alleles separates during gamete formation
  • Law of Independent Assortment: alleles for different genes are sorted independently
  • Law of Dominance: one allele can be dominant over another
• Punnett Squares: diagrams used to predict the probability of inheritance of certain traits

Molecular Genetics

• Central Dogma: DNA → RNA → Protein
• Transcription: the process of creating RNA from DNA
• Translation: the process of creating protein from RNA

Genetic Variation

• Mutations: changes in the DNA sequence
• Types of mutations:
  • Point mutations: single nucleotide change
  • Frameshift mutations: insertion or deletion of nucleotides
  • Chromosomal mutations: changes in the number or structure of chromosomes
• Genetic drift: random change in the frequency of a gene or genetic trait in a population

Gene Expression

• Epigenetics: the study of gene expression and regulation
• Gene regulation: the control of gene expression in response to environmental cues
• Mechanisms of gene regulation:
  • Transcriptional regulation: controlling gene expression at the transcription level
  • Post-transcriptional regulation: controlling gene expression after transcription

DNA Structure

• The double helix model consists of two complementary strands of nucleotides twisted together
• A nucleotide is composed of a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base (A, C, G, or T)

Genes and Genomes

• A gene is a segment of DNA that codes for a protein or functional RNA
• The human genome consists of approximately 20,000-25,000 protein-coding genes
• The genome is the complete set of genes in an organism

Mendelian Genetics

• The Law of Segregation states that each pair of alleles separates during gamete formation
• The Law of Independent Assortment states that alleles for different genes are sorted independently
• The Law of Dominance states that one allele can be dominant over another
• Punnett Squares are diagrams used to predict the probability of inheritance of certain traits

Molecular Genetics

• The Central Dogma states that DNA is transcribed into RNA, which is then translated into Protein
• Transcription is the process of creating RNA from DNA
• Translation is the process of creating protein from RNA

Genetic Variation

• Mutations are changes in the DNA sequence
• Point mutations involve a single nucleotide change
• Frameshift mutations involve the insertion or deletion of nucleotides
• Chromosomal mutations involve changes in the number or structure of chromosomes
• Genetic drift is a random change in the frequency of a gene or genetic trait in a population

Gene Expression

• Epigenetics is the study of gene expression and regulation
• Gene regulation is the control of gene expression in response to environmental cues
• Transcriptional regulation controls gene expression at the transcription level
• Post-transcriptional regulation controls gene expression after transcription

Test your knowledge of genetics, covering DNA structure, genes, genomes, and Mendelian genetics principles. Learn about the double helix model, nucleotides, and the laws of inheritance.